How long will a 10 second youtube intro take to render? I have had it rendering for hours upon hours and it all seems too much!
It depends a lot on the scene.  As a starting point, I would recommend rendering one frame and see how long that takes.  If your animation is 10 seconds and you are rendering at 24 frames per second then your whole animation will be 240 frames.  If it takes one hour per frame then your whole animation will take 240 hours or 10 days.  Of course, I'm assuming a lot without knowing about your scene.

The actual time it takes could vary greatly from my estimate.